Biomolecules is a chapter in the CBSE Class 12 Chemistry syllabus from Chemistry - II. This chapter hub brings together revision notes, practice questions, worksheets, flashcards, formula sheet to help students learn, practice, and revise Biomolecules effectively.

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Biomolecules

NCERT Class 12 Chemistry Chapter 5: Biomolecules (Pages 281–302)

Class 12 CBSE hub Chemistry chapters Chemistry - II

Biomolecules at a Glance

Board

CBSE

Class

Class 12

Subject

Chemistry

Book

Chemistry - II

Chapter

Pages

281–302

Resources

7 study resources

Biomolecules Revision Guide

Download the Biomolecules revision guide with key points, summaries, and quick revision notes for CBSE Class 12 Chemistry.

Key Points

Definition of biomolecules.

Biomolecules are organic molecules essential for life, including carbohydrates, proteins, and nucleic acids.

Carbohydrates and general formula.

They are organic compounds with a general formula Cx(H2O)y, primarily yielding energy.

Types of carbohydrates.

Carbohydrates are classified as monosaccharides, oligosaccharides, and polysaccharides based on hydrolysis.

Monosaccharides.

Simple sugars like glucose and fructose cannot be hydrolyzed further, serving as energy sources.

Disaccharides.

Formed from two monosaccharides, e.g., sucrose and lactose, linked by glycosidic bonds.

Polysaccharides.

Long chains of monosaccharides; starch and cellulose are examples; serve as energy storage or structure.

Peptide bonds in proteins.

Proteins are polymers of amino acids connected via peptide bonds, crucial for structure and function.

Amino acid classification.

Amino acids can be essential (diet needed) or non-essential (synthesized by the body).

Protein structure levels.

Proteins have four structures: primary, secondary, tertiary, and quaternary, dictating functionality.

Denaturation of proteins.

Denaturation alters protein structure via heat or pH change, impacting its biological activity.

Enzymes as biocatalysts.

Enzymes, often proteins, catalyze biochemical reactions, lowering activation energy for efficiency.

Definition of nucleic acids.

Nucleic acids (DNA and RNA) are polymers of nucleotides, essential for genetic information transfer.

DNA structure.

DNA is double-stranded, featuring a sugar-phosphate backbone and base pairs: A-T and C-G.

RNA types and functions.

Types include mRNA, rRNA, and tRNA, each playing roles in protein synthesis and genetic expression.

Vitamins in diet.

Vitamins are organic compounds essential in small amounts; deficiency leads to diseases.

Fat-soluble vs water-soluble vitamins.

Fat-soluble vitamins (A, D, E, K) are stored, while water-soluble (B, C) must be consumed regularly.

Insulin's role.

Insulin regulates blood glucose levels, showcasing hormonal function in maintaining homeostasis.

Role of genes.

Genes, made of DNA, dictate inherited traits and protein synthesis, crucial for organismal identity.

Importance of ribose and deoxyribose.

Ribose in RNA and deoxyribose in DNA form the sugar backbone, influencing genetic coding.

Function of hormones.

Hormones are signaling molecules that regulate physiological processes, crucial for homeostasis in organisms.

Biomolecules Practice Questions & Answers

Practice important questions and exam-style problems from Biomolecules. These questions cover key topics from the CBSE Class 12 Chemistry syllabus.

How to practice: Start with the questions below to test your understanding of Biomolecules. Use the revision guide to review concepts you find difficult, then come back and retry the questions for better retention.

What is the molecular formula of glucose?

Single Answer MCQ

Q-00083850

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Which of the following is a storage polysaccharide in plants?

Single Answer MCQ

Q-00083851

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What type of linkage connects the monosaccharide units in starch?

Single Answer MCQ

Q-00083852

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Which sugar is commonly known as milk sugar?

Single Answer MCQ

Q-00083853

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What is the main structural component of plant cell walls?

Single Answer MCQ

Q-00083854

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How does glucose react with hydroxylamine?

Single Answer MCQ

Q-00083855

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What type of carbohydrate is glycogen primarily classified as?

Single Answer MCQ

Q-00083856

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What type of reaction yields gluconic acid from glucose?

Single Answer MCQ

Q-00083857

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View all 96 Biomolecules questions

Which carbohydrate is noted for having a branched structure?

D-Glucose is classified based on its relationship to what molecule?

What is the major difference between cellulose and starch?

What is the primary function of carbohydrates in living organisms?

How many -OH groups does glucose possess?

What distinguishes a reducing sugar from a non-reducing sugar?

Which of the following can be produced from the hydrolysis of starch?

Which of the following best describes enzymes?

What suffix is commonly used in the names of enzymes?

Which factor does NOT affect enzyme activity?

Which of the following enzymes hydrolyzes maltose into glucose?

Enzymes lower the activation energy of a reaction. What is the consequence?

What type of enzyme catalyzes the transfer of phosphate groups?

What happens to enzymes after they catalyze a reaction?

Why are enzymes considered specific to their substrates?

Which condition typically leads to enzyme denaturation?

What is the function of coenzymes in enzyme activity?

Which enzyme is responsible for the oxidation of substrates?

Enzymes are proteins that can act under mild conditions. What advantage does this provide?

The enzyme sucrase catalyzes the hydrolysis of sucrose. What are the products formed?

A particular enzyme loses its activity at high temperatures. This enzyme is likely to be:

Which of the following describes enzyme-substrate interaction?

Why are enzymes considered biocatalysts?

What is the primary role of insulin in the body?

Which hormone is primarily involved in the body's response to stress?

Which hormone regulates the metabolism of carbohydrates, fats, and proteins?

What type of molecule is adrenaline?

Which of the following is a function of glucagon?

What condition results from the overproduction of thyroxine?

What hormone is responsible for the regulation of the menstrual cycle?

Which hormone is released by the adrenal medulla during stressful situations?

What is the role of growth hormone in the body?

How does the endocrine system primarily transmit hormones?

Which gland is known as the 'master gland' of the endocrine system?

What is Addison's disease related to?

Which of the following hormones primarily stimulates the metabolism of calcium?

Which type of hormone is testosterone?

What triggers the release of insulin?

How do steroid hormones exert their effects?

What is the primary function of nucleic acids?

Which nitrogenous base is found in RNA but not in DNA?

What type of bond forms between nucleotides in a nucleic acid chain?

Which of the following statements about DNA is correct?

What is the primary component of the backbone of DNA?

Which process involves the synthesis of mRNA from a DNA template?

In which part of the cell does transcription primarily occur?

What type of RNA is responsible for carrying amino acids to the ribosome during protein synthesis?

Which of the following is a characteristic of RNA?

Which base pairs with adenine in DNA?

What is the role of ribosomal RNA (rRNA)?

Which of the following best describes a nucleotide?

During replication, which enzyme is primarily responsible for unwinding the DNA double helix?

In terms of structure, what distinguishes RNA from DNA?

What type of bond holds together complementary base pairs in DNA?

Which type of RNA carries instructions from DNA for protein synthesis?

What is the primary structure of a protein?

Which of the following bonds stabilizes the secondary structure of proteins?

What type of protein structure is characterized by pleated sheets?

Which type of protein is known for having a spherical shape?

What occurs to a protein during denaturation?

In proteins, what stabilizes the tertiary structure?

Which structural level of a protein is not seen in proteins made of a single polypeptide chain?

Which of the following can cause protein denaturation?

What primarily determines the unique shape and function of a protein?

Which type of bond links amino acids together in a protein?

Which of the following is not a function of proteins?

Which protein structure involves multiple subunits?

What is the effect of reducing agents on disulfide bonds in proteins?

Which method can be used to determine protein concentration in a solution?

Which of the following describes enzymes?

Proteins lose their function when their structure is altered. This is known as:

Which vitamin is primarily involved in vision and immune function?

Which vitamin is known as ascorbic acid and is critical for collagen synthesis?

Which fat-soluble vitamin is essential for calcium absorption and bone health?

What deficiency disease results from a lack of Vitamin B1?

Which vitamin is known for its blood-clotting properties?

Which of the following vitamins is water-soluble?

Excess intake of which vitamin can lead to toxicity, especially in the context of supplements?

What is a primary source of Vitamin D in the human diet?

Which of the following vitamins do not need to be consumed daily due to storage in the body?

Which vitamin is primarily known for its antioxidant properties?

Which vitamin is associated with the prevention of neural tube defects during pregnancy?

What is the role of Vitamin B12 in the body?

Which of the following vitamins must typically be ingested through dietary sources as the body cannot synthesize it?

What is a common dietary source of Vitamin B6?

Vitamin D is synthesized in the skin upon exposure to what?

Which vitamin is referred to as the anti-stress vitamin?

What deficiency is caused by a lack of Vitamin C?

Single Answer MCQ

Q-00083967

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Biomolecules Practice Worksheets

Download and practice Biomolecules worksheets to improve problem-solving accuracy and speed for CBSE Class 12 Chemistry exams.

Biomolecules - Practice Worksheet

This worksheet covers essential long-answer questions to help you build confidence in Biomolecules from Chemistry - II for Class 12 (Chemistry).

Practice

Questions

Define carbohydrates and explain their classifications with appropriate examples.

Carbohydrates are organic compounds made of carbon, hydrogen, and oxygen, generally with the formula Cx(H2O)y. They are classified into three categories: monosaccharides (like glucose and fructose), oligosaccharides (like sucrose and maltose), and polysaccharides (like starch and cellulose). Monosaccharides are the simplest form of carbohydrates, consisting of single sugar units. Oligosaccharides comprise 2-10 monosaccharide units linked together, while polysaccharides are complex carbohydrates containing numerous monosaccharide units. Each class plays unique roles in biological systems, such as energy storage and structural support.

Explain the structure and function of proteins, including their amino acid composition.

Proteins are polymers of amino acids linked by peptide bonds. Each amino acid consists of an amino group (–NH2), a carboxyl group (–COOH), a hydrogen atom, and a variable side chain (R group). There are 20 standard amino acids, linked in specific sequences to form proteins. The primary structure is the sequence of amino acids, secondary structure includes alpha helices and beta sheets, tertiary structure is the overall folding of the protein, and quaternary structure involves multiple polypeptide chains. Proteins perform various functions such as catalysis (enzymes), transport (hemoglobin), and structural support (collagen).

Differentiate between DNA and RNA in terms of structure and function.

DNA (deoxyribonucleic acid) and RNA (ribonucleic acid) are both nucleic acids but differ in structure and function. DNA is a double-stranded helix with deoxyribose sugar and thymine as one of its bases, while RNA is typically single-stranded with ribose sugar and uracil replacing thymine. DNA stores genetic information and is stable for long-term information storage, whereas RNA is involved in protein synthesis and is more versatile in function. The base pairing differs: in DNA, adenine pairs with thymine, while in RNA adenine pairs with uracil.

Describe the process of enzyme action and its significance in biochemical reactions.

Enzymes are biological catalysts that accelerate biochemical reactions by lowering the activation energy required for the reaction to proceed. They work by binding substrates at their active sites, forming an enzyme-substrate complex, leading to the transformation of substrates into products. Enzymes are highly specific for their substrates and can be affected by factors such as temperature, pH, and concentration. This specificity and efficiency make enzymes essential in metabolic pathways, helping to regulate and facilitate numerous physiological processes.

What are vitamins and why are they essential for human health? Classify them based on solubility.

Vitamins are organic compounds required in small amounts for various biochemical functions in the body. They are essential because they cannot be synthesized in sufficient quantities by the body. Vitamins can be classified as fat-soluble (A, D, E, K) or water-soluble (C and B-complex). Fat-soluble vitamins are stored in body fat, while water-soluble vitamins must be regularly consumed as they are excreted quickly. Deficiencies in vitamins can lead to various health issues, highlighting their importance in diet.

Explain how carbohydrates serve as energy sources in the human body.

Carbohydrates are primary energy sources for the body, mostly obtained from dietary sources such as grains, fruits, and vegetables. They are broken down into glucose through digestion. Glucose is then metabolized through glycolysis and the citric acid cycle to produce ATP, the energy currency of the cell. Excess glucose can be stored as glycogen in the liver and muscles for later use. Carbohydrates not only provide energy but also play a role in cell recognition and structure.

Describe the role of nucleic acids in heredity and protein synthesis.

Nucleic acids, including DNA and RNA, play critical roles in heredity and protein synthesis. DNA contains the genetic blueprint of an organism, guiding cell development and function. During replication, DNA is copied to ensure that genetic information is passed to daughter cells. Protein synthesis involves two key processes: transcription (conversion of DNA to mRNA) and translation (mRNA is translated into amino acid sequences by ribosomes). Thus, nucleic acids are fundamental to biological inheritance and the functioning of all living organisms.

What is the significance of glucose in cellular metabolism?

Glucose is a crucial energy source for cellular metabolism, serving as the primary fuel for cells. During cellular respiration, glucose is processed to produce ATP, which powers various cellular functions. It also serves as a building block for other biomolecules, including nucleotides, amino acids, and lipids. Elevated glucose levels can lead to conditions like diabetes if not properly regulated, while low glucose levels can affect energy availability, illustrating its importance in metabolism.

Define lipids and discuss their structural characteristics and functions.

Lipids are a diverse group of hydrophobic organic compounds, including fats, oils, and phospholipids. Structurally, they are characterized by long hydrocarbon chains or rings and are not soluble in water. Lipids play essential roles in the body, including energy storage, structural components of cell membranes, insulation, and signaling molecules (hormones). They can be classified into simple lipids ( triglycerides) and complex lipids (phospholipids and steroids), each serving unique functions.

Examine the process of hydrolysis and its importance in biochemical reactions.

Hydrolysis is a chemical process where water is used to break down compounds, such as carbohydrates and proteins. In biological systems, hydrolysis is essential for the digestion of macromolecules, converting them into absorbable units. For example, polysaccharides like starch undergo hydrolysis to produce monosaccharides like glucose, which can be utilized for energy. Proteins are similarly hydrolyzed into amino acids. This process is crucial for metabolic pathways and nutrient absorption.

Biomolecules - Mastery Worksheet

This worksheet challenges you with deeper, multi-concept long-answer questions from Biomolecules to prepare for higher-weightage questions in Class 12.

Mastery

Questions

Discuss the classification of carbohydrates, providing specific examples for each group and their biological importance.

Carbohydrates are categorized into three main types: monosaccharides (e.g., glucose), disaccharides (e.g., sucrose), and polysaccharides (e.g., starch). Monosaccharides are simple sugars and serve as energy sources; disaccharides are formed from two monosaccharides, contributing to energy storage; polysaccharides serve as energy reserves and structural components in plants (like cellulose).

Explain the structural differences between DNA and RNA, and discuss how these differences relate to their functions in cellular processes.

DNA consists of a deoxyribose sugar, thymine base, and is double-stranded, while RNA contains ribose sugar, uracil base, and is single-stranded. These structural differences allow DNA to store genetic information reliably and RNA to function as a messenger for protein synthesis.

Describe the process of enzyme catalysis, including the role of the active site, substrate specificity, and factors affecting enzyme activity.

Enzymes lower the activation energy for reactions by binding substrates at their active site, forming an enzyme-substrate complex. This specific interaction promotes the conversion of substrates to products. Factors such as temperature, pH, and substrate concentration influence enzymatic activity.

Detail the significance of vitamins in biological systems, categorizing them into water-soluble and fat-soluble groups, with examples for each.

Vitamins act as coenzymes or precursors in vital biochemical reactions. Water-soluble vitamins (e.g., B and C) are excreted easily and must be consumed regularly, while fat-soluble vitamins (e.g., A, D, E, K) can be stored in body fat. Deficiencies in these nutrients can lead to specific health issues.

Compare and contrast the structures and functions of fibrous and globular proteins, providing examples.

Fibrous proteins (e.g., collagen) have elongated structures and provide structural support, whereas globular proteins (e.g., enzymes) are compact, soluble and functional. Fibrous proteins are generally less soluble in water, while globular proteins perform numerous roles including catalysis and transport.

Illustrate the cyclic structure of glucose and how it explains its reactivity compared to its open chain form.

Cyclic glucose exists predominantly as a six-membered ring (pyranose) formed by the reaction of an -OH group with the aldehyde, influencing its reactivity and accessibility for biological processes. This structure stabilizes glucose and allows it to participate in glycogen and starch formation.

Identify the roles of hormones in biological systems, detailing the mechanism of action for at least two different types of hormones.

Hormones like insulin (a peptide hormone) regulate glucose levels by promoting uptake in cells, while steroid hormones like cortisol affect metabolism by regulating gene expression. They act through receptor binding and signal transduction pathways, which alter physiological responses.

Discuss the concept of reducing and non-reducing sugars, providing examples and explaining their significance in biochemical pathways.

Reducing sugars (like glucose and fructose) have free aldehyde or ketone groups that can reduce other substances, while non-reducing sugars (like sucrose) do not. This classification is crucial in carbohydrate metabolism and food chemistry.

Examine the roles of nucleic acids in heredity and protein synthesis, explaining how structure dictates function in DNA and RNA.

DNA serves as the heritable genetic material, containing instructions for protein synthesis, while RNA translates these instructions into proteins. The structural differences between DNA (double helix, stable) and RNA (single strand, more versatile) underscore their different roles.

Evaluate the importance of amino acid classification on protein structure and function, providing examples of essential versus non-essential amino acids.

Amino acids can be classified as essential (must be obtained via diet, e.g., leucine) or non-essential (can be synthesized by the body, e.g., alanine). This classification affects protein synthesis and nutrition; lack of essential amino acids can impair enzyme function and muscle synthesis.

Biomolecules - Challenge Worksheet

The final worksheet presents challenging long-answer questions that test your depth of understanding and exam-readiness for Biomolecules in Class 12.

Challenge

Questions

Analyze the role of carbohydrates in energy metabolism and discuss how their structure influences their function in living organisms.

Consider exploring the varying structures of monosaccharides and polysaccharides, and how these structures relate to their roles in energy storage and release.

Discuss the significance of enzymes in biochemical reactions and evaluate the factors that affect enzyme activity.

Include examples of specific enzymes and relate how temperature, pH, and substrate concentration influence their efficiency.

Compare and contrast DNA and RNA, focusing on their structures, functions, and roles in protein synthesis.

Reflect on the structural differences, such as the types of sugars and nitrogenous bases, and how these differences affect their respective functions.

Evaluate how the denaturation of proteins affects their functionality, providing examples of both thermal and chemical denaturation.

Discuss the implications of denaturation in biological systems, including examples such as enzyme activity and structural proteins.

Examine the various classifications of lipids and their functions in biological membranes.

Include discussions on phospholipids, steroids, and triglycerides, and how their unique structures contribute to their diverse functionalities.

Critique the importance of vitamins in human health, focusing on their classification and the role they play in metabolic processes.

Examine both fat-soluble and water-soluble vitamins, and discuss the consequences of deficiencies for various vitamins.

Investigate the mechanisms of action of hormones and their effect on physiological processes, using specific hormonal examples.

Discuss the role of hormones such as insulin and adrenaline, focusing on how their binding to receptors leads to cellular responses.

Analyze the statement: 'The unique structure of proteins determines their function.' Provide examples supporting or contrasting this claim.

Include examples that demonstrate how structural changes lead to functional changes, such as in hemoglobin or enzymes.

Explore the relationship between the structure of nucleic acids and their function in genetic information storage and transmission.

Discuss aspects such as base pairing, double helix formation in DNA, and the role of mRNA in transcription.

Hypothesize on the potential consequences of disrupting the balance of biomolecules in the human body, using specific examples.

Evaluate the effects of high carbohydrate intake versus low protein intake, and how these can lead to health issues.

Biomolecules Formula Sheet

Use this Class 12 Chemistry Biomolecules Formula Sheet for quick revision before school exams and CBSE exams. It brings together the important formulas, key concepts, and worked examples in one place so students can revise faster and download a printable PDF for offline study.

Important Formulas

C_n(H_2O)_n

This is the general formula of carbohydrates where n is the number of carbon atoms. It indicates that carbohydrates are hydrates of carbon and helps classify compounds as carbohydrates.

R-COOH + R'-NH2 → R-CONHR' + H2O

This is the reaction that forms a peptide bond between two amino acids. R-COOH is the carboxylic acid part of an amino acid and R'-NH2 is the amino group of another amino acid.

n(C_nH_{2n}O_n) → (C_nH_{2n}O_n)_n

This relation indicates how several monosaccharides (C_nH_{2n}O_n) can combine to form a polysaccharide (polymeric form). It highlights the concept of polymerization in carbohydrates.

C_6H_{12}O_6

This is the molecular formula of glucose, an important monosaccharide. It represents a primary source of energy in biological systems.

E_n = m \cdot g \cdot h

This represents the potential energy in biological systems where 'E' is energy, 'm' is mass, 'g' is acceleration due to gravity, and 'h' is height. This relates to energy changes during biochemical reactions.

Sucrose + H2O → Glucose + Fructose

This is a hydrolysis reaction where sucrose (disaccharide) breaks down into glucose and fructose (monosaccharides) in the presence of water.

Glycogen + n H2O → Glucose (n)

Glycogen hydrolysis converts stored energy in glycogen into glucose units, which can be utilized for energy release.

C12H22O11 + H2O → C6H12O6 + C6H12O6

This is another representation of the hydrolysis of sucrose to form two molecules of glucose during digestion.

2 amino acids → Dipeptide + H2O

This represents the condensation reaction where two amino acids combine to form a dipeptide, releasing a molecule of water.

DNA → Nucleotide + Nucleotide + ...

This expresses the polymerization of nucleotides to form a nucleic acid like DNA, which is critical for genetic information storage.

Worked Examples

C_n(H_2O)_n → Monosaccharides + H2O (for n >= 3)

This equation describes the hydrolysis of polysaccharides into monosaccharides, showcasing the breakdown of complex carbohydrates.

R-COOH + R'-NH2 → R-CONHR' + H2O

This reaction illustrates peptide bond formation between amino acids, essential for protein synthesis.

C6H12O6 + 6 O2 → 6 CO2 + 6 H2O + Energy (ATP)

This equation represents cellular respiration where glucose is oxidized to produce carbon dioxide, water, and energy.

C6H12O6 → 2 C2H5OH + 2 CO2

This is the equation for fermentation, converting glucose into ethanol and carbon dioxide, relevant in alcohol production.

n(Amino acid) → Polypeptide + H2O

This depicts how multiple amino acids are combined into a polypeptide chain through peptide bond formation.

A-Base + B-Base ↔ A-B

This represents the base pairing in nucleic acids (Adenine pairs with Thymine/Uracil), crucial for DNA/RNA stability.

Carbohydrates + H2O → Monosaccharides (Hydrolysis)

This shows the general hydrolysis of carbohydrates, providing simpler sugar units.

Fat soluble vitamins: A, D, E, K

This classification helps in the understanding of vitamin solubility, affecting absorption and storage in the body.

Water soluble vitamins: B, C

This indicates that these vitamins must be consumed regularly due to their limited storage in the body.

Cholesterol + Enzymes → Hormones

This represents the transformation of cholesterol into various steroid hormones through enzymatic action in the body.

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Biomolecules Frequently Asked Questions

Master the key concepts of biomolecules including carbohydrates, proteins, nucleic acids, and hormones. Understand their structures, functions, and significance in living systems as covered in Class 12 Chemistry.

QWhat are biomolecules?

Biomolecules are organic molecules that are essential for life. They include carbohydrates, proteins, lipids, and nucleic acids. These molecules interact to perform vital functions in living organisms, supporting growth, energy storage, and information transfer.

QHow are carbohydrates classified?

Carbohydrates are classified based on their molecular structure and hydrolysis behavior into three main groups: monosaccharides (single sugar units), oligosaccharides (2-10 monosaccharides), and polysaccharides (long chains of monosaccharides).

QWhat is the general formula for carbohydrates?

Carbohydrates generally follow the empirical formula Cx(H2O)y. For example, glucose has the molecular formula C6H12O6, which fits into this general formula, highlighting the relationship between carbon and water.

QWhat are monosaccharides?

Monosaccharides are the simplest form of carbohydrates, consisting of single sugar units, such as glucose, fructose, and ribose. They cannot be hydrolyzed into simpler sugars and are crucial for various biological processes.

QWhat distinguishes oligosaccharides from polysaccharides?

Oligosaccharides consist of 2 to 10 monosaccharide units linked by glycosidic bonds, while polysaccharides are large molecules composed of many monosaccharides (often hundreds or thousands). Polysaccharides serve as energy storage or structural materials.

QWhat is the role of proteins in living organisms?

Proteins play critical roles in biological processes, including serving as enzymes, structural components, and transport molecules. They are made from amino acids linked by peptide bonds and perform diverse functions essential for life.

QHow are amino acids classified?

Amino acids are classified based on the nature of their side chains. They can be categorized as nonpolar, polar uncharged, polar charged, basic, or acidic. This classification affects how they interact within proteins.

QWhat is denaturation in proteins?

Denaturation is the process where proteins lose their native structure due to external factors like heat or pH changes, resulting in the loss of biological activity. While primary structure remains intact, secondary and tertiary structures are disrupted.

QWhat is a glycosidic linkage?

A glycosidic linkage is a type of covalent bond that joins monosaccharides together to form disaccharides or polysaccharides. It occurs through a condensation reaction where a water molecule is released.

QHow do enzymes function?

Enzymes function as biocatalysts that speed up biochemical reactions by lowering the activation energy required. They are specific to their substrates and can significantly increase the rate of reactions in living organisms.

QWhat are vitamins and why are they important?

Vitamins are organic compounds required in small quantities for various metabolic processes. They play crucial roles in health, facilitating bodily functions and preventing deficiency diseases. Some vitamins must be obtained through diet.

QWhat constitutes nucleic acids?

Nucleic acids, such as DNA and RNA, are polymers made from nucleotide monomers, consisting of a sugar, phosphate group, and nitrogenous base. They are vital for storing and transmitting genetic information.

QWhat is the difference between DNA and RNA?

DNA (deoxyribonucleic acid) is double-stranded and contains the sugar deoxyribose with thymine as a base, while RNA (ribonucleic acid) is usually single-stranded, contains ribose, and has uracil instead of thymine.

QHow do hormones function in the body?

Hormones function as intercellular messengers produced by endocrine glands. They regulate various physiological processes by binding to specific receptors on target cells, thus influencing functions like metabolism and growth.

QWhat role do nucleic acids play in heredity?

Nucleic acids are responsible for heredity as they carry genetic information from one generation to the next. DNA replicates during cell division, ensuring genetic continuity, while RNA aids in protein synthesis.

QWhat are reducing and non-reducing sugars?

Reducing sugars are carbohydrates that can donate electrons to other molecules (e.g., glucose, fructose), whereas non-reducing sugars (e.g., sucrose) do not have free aldehyde or ketone groups under physiological conditions.

QWhat is glycogen, and where is it found?

Glycogen is a polysaccharide that serves as the main energy storage form in animals. It is primarily found in the liver and muscles, where it can be quickly converted to glucose when energy is needed.

QWhy is cellulose important?

Cellulose is a polysaccharide that is a critical component of plant cell walls, providing structural support. Unlike starch, it is not digestible by humans, but it contributes to dietary fiber, which aids digestion.

QWhat is the significance of hormones in growth?

Hormones like growth hormone and sex hormones (testosterone and estrogen) play vital roles in regulating growth, development, and metabolism. They influence pubertal changes, muscle development, and overall physical growth.

QHow do carbohydrates function in energy storage?

Carbohydrates serve as a primary energy source for living organisms. In plants, they are stored as starch, while in animals, they are stored as glycogen. Both forms can be readily converted to glucose when energy is required.

QWhat is meant by the term 'primary structure' in proteins?

The primary structure of a protein refers to its specific sequence of amino acids linked by peptide bonds. This sequence determines the protein's unique characteristics and functions.

QHow does an enzyme's structure affect its function?

An enzyme's structure, particularly its active site shape, is crucial for its function. The specific conformation allows enzymes to bind to their substrate(s) precisely, facilitating the biochemical reaction and ensuring efficiency.

QWhat influences the solubility of vitamins?

Vitamins are classified based on their solubility: fat-soluble vitamins (A, D, E, K) dissolve in fats and oils, while water-soluble vitamins (B-complex, C) dissolve in water. Their solubility affects their absorption and storage in the body.

QWhat is the function of ribosomes in protein synthesis?

Ribosomes are cellular structures where protein synthesis occurs. They read mRNA sequences and facilitate the binding of amino acids brought by tRNA, linking them together to form polypeptides, which ultimately fold into functional proteins.

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Biomolecules Flashcards

Revise key terms and definitions from Biomolecules with interactive flashcards. Quick recall practice for CBSE Class 12 Chemistry.

These flash cards cover important concepts from Biomolecules in Chemistry - II for Class 12 (Chemistry).

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What are biomolecules?

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Biomolecules are complex molecules that are essential for life processes, including carbohydrates, proteins, nucleic acids, and lipids.

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Define carbohydrates.

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Carbohydrates are organic compounds consisting of carbon, hydrogen, and oxygen, typically following the general formula Cx(H2O)y.

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What is the general formula for carbohydrates?

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Most carbohydrates have the general formula Cx(H2O)y, indicating their composition of carbon and water.

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Examples of common carbohydrates?

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Common carbohydrates include glucose, sucrose, starch, and lactose.

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What are monosaccharides?

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Monosaccharides are simple carbohydrates that cannot be hydrolyzed into smaller units. Examples include glucose and fructose.

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What defines oligosaccharides?

6/20

Oligosaccharides consist of 2 to 10 monosaccharide units linked together; disaccharides like sucrose are a common type.

7/20

Define polysaccharides.

7/20

Polysaccharides are large molecules consisting of numerous monosaccharide units, such as starch and cellulose.

8/20

Difference between reducing and non-reducing sugars?

8/20

Reducing sugars can reduce Fehling’s and Tollens’ reagents; all monosaccharides are reducing sugars, while some disaccharides are not.

9/20

What are aldoses and ketoses?

9/20

Aldoses contain an aldehyde group, while ketoses contain a keto group. Both are types of monosaccharides.

10/20

What is sucrose?

10/20

Sucrose is a common disaccharide composed of glucose and fructose, used widely as table sugar.

11/20

What is the role of carbohydrates in the body?

11/20

Carbohydrates provide energy, serve as structural components, and play a role in cellular signaling.

12/20

Define the term 'saccharides'.

12/20

Saccharides are another term for carbohydrates, derived from the Greek word 'sakcharon', meaning sugar.

13/20

What is the common name for lactose?

13/20

Lactose is known as milk sugar, found in milk and dairy products.

14/20

Explain hydrolysis in carbohydrates.

14/20

Hydrolysis is the chemical reaction that breaks down carbohydrates into simpler sugars by adding water.

15/20

Classify carbohydrates based on hydrolysis.

15/20

Carbohydrates can be classified as monosaccharides, oligosaccharides, and polysaccharides based on how they respond to hydrolysis.

16/20

Why are some carbohydrates sweet?

16/20

Carbohydrates that taste sweet are typically monosaccharides or disaccharides due to their structure and chemical properties.

17/20

What is starch?

17/20

Starch is a polysaccharide composed of glucose units and serves as a major energy storage form in plants.

18/20

Define glycogen.

18/20

Glycogen is a polysaccharide that serves as a form of energy storage in animals and is made up of glucose units.

19/20

What is the significance of cellulose?

19/20

Cellulose is a polysaccharide that provides structural support in plant cell walls and is not digestible by humans.

20/20

Common mistake regarding carbohydrates?

20/20

A common mistake is to assume all compounds fitting Cx(H2O)y are carbohydrates; some, like acetic acid, are not.

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